Patents-in-trust refers to a legal arrangement that holds land in trust for Native American tribes, ensuring that the land remains under tribal control and cannot be sold or transferred without tribal consent. This concept emerged as a way to protect tribal lands from the negative impacts of allotment policies, which aimed to individualize land ownership and often led to significant land loss for tribes. By placing land into trust, tribes can maintain sovereignty over their territory, preserving cultural practices and community cohesion.